Start with the quality of discovery
A strong development company should ask about users, workflows, constraints, existing systems, success measures and what must be true for the project to create value. A proposal produced before those questions are understood is usually based on assumptions.
Good discovery also identifies what should not be built in the first release. A smaller validated scope is often more useful than a long feature list that hides the riskiest decisions.
Ask for evidence that matches your type of problem
A beautiful portfolio is useful, but context matters more. Look for case studies or demonstrations that explain the challenge, architecture, integrations, roles, deployment or operational workflow behind the interface.
The closest evidence may come from a different industry if the underlying problem is similar, such as bookings, approvals, inventory, permissions, dashboards or recurring SaaS workflows.
Clarify ownership before development begins
Confirm source-code access, repository ownership, hosting accounts, domains, third-party services, credentials, design files, documentation and the handover process.
Ownership should be written into the proposal or agreement. A business should not discover at launch that an essential account or codebase is controlled only by a supplier.
Evaluate communication as part of engineering quality
Software projects contain uncertainty. You need a team that surfaces risks early, explains alternatives and demonstrates working progress instead of hiding behind status reports.
Agree on how often progress is reviewed, who makes product decisions, where requirements are recorded and how scope changes are handled.
Understand the plan after launch
Launching is not the end of a software product. Ask who handles monitoring, security updates, bug fixes, backups, analytics, infrastructure changes and future releases.
A credible partner should be able to explain the maintenance boundary even if you decide to manage the system internally after handover.